what is the ecg abnormality

Reading File

Finding Sources

Reading File

Loading Image

Based on careful analysis of the uploaded ECG and comparison with the textbook WPW reference image, here is my interpretation:

ECG Abnormality: Wolff-Parkinson-White (WPW) Pattern

The ECG shown belongs to a female patient, heart rate ~70 bpm, and demonstrates the classic triad of ventricular pre-excitation:

Three Key Findings

Feature	What to Look For	Finding in This ECG
Short PR interval	< 120 ms (< 3 small squares)	PR interval is shortened across all leads
Delta wave	Slurred, slow upstroke at the start of the QRS	Visible as a broad, notched initial deflection before the sharp QRS peak
Widened QRS	> 120 ms due to ventricular fusion	QRS complexes appear broad/slurred compared to normal

What is Happening Physiologically?

In WPW, an accessory pathway (Bundle of Kent) bypasses the AV node and connects the atria directly to the ventricles. The impulse:

Travels down the accessory pathway faster than through the AV node (shortening the PR interval)
Begins depolarizing part of the ventricle early via this abnormal route (creating the delta wave - slurred QRS upstroke)
Fuses with the normal His-Purkinje conduction, producing a widened hybrid QRS complex

Secondary ST-T changes (discordant T waves) are also typically present, as seen here.

Lead-by-Lead Clues in This ECG

V1-V3: Prominent delta waves with broad QRS - typical of a left-sided accessory pathway (type A WPW pattern)
Inferior leads (II, III, aVF): Upright delta waves
aVR: Negative delta wave (expected)

Clinical Significance

Dysrhythmias occur in ~50% of WPW patients - most commonly orthodromic AVRT (narrow complex SVT)
Risk of atrial fibrillation conducting rapidly through the accessory pathway, potentially causing ventricular fibrillation and sudden death
Avoid: Verapamil, digoxin, and adenosine in AF with WPW (can accelerate accessory pathway conduction and precipitate VF)
Definitive treatment: Radiofrequency catheter ablation of the accessory pathway

Source: Tintinalli's Emergency Medicine, pp. 159-161 (WPW ECG triad and management)

Disclaimer: This interpretation is for educational purposes. Clinical correlation and formal cardiology review are required for patient management decisions.

This is a shared conversation. Sign in to Orris to start your own chat.